Structure and mechanical behavior of submicrocrystalline /spl alpha/-Fe

摘要

Structural state, character of plastic flow at various scale levels and mechanical properties of /spl alpha/-Fe subjected to equichannel angular pressing by different deformation routes with subsequent annealing were studied with transmission electron, optical and scanning tunnelling microscopes. It was determined that submicrocrystalline structure causes great localization of deformation near the ends of the specimen. At the same time the most of working part of the specimens remains almost undeformed. Plastic flow is realized by the development of localized deformation meso- and macrobands. The character of propagation of meso- and macrobands governs the shape of stress-strain curves. The annealing of submicrocrystalline /spl alpha/-Fe specimens in the temperature range [523-723] K results in delocalization of plastic deformation.